Which of the following changes would improve the accuracy of the arterial velocity?

1. Line density is directly related to the:

 

a. imaging depth

b. temporal resolution

c. pulse repetition period

d. pulse repetition frequency

2. Which of the following are even harmonic frequencies of a 2-MHz transducer?

a. 2, 4, 6

b. 3, 5, 7

c. 4, 6, 8

d. 4, 8, 12

3. Which of the following will most likely occur if the pulse repetition frequency is set too high?

a. flash

b. aliasing

c. acoustic speckle

d. range ambiguity

 

4. Which of the following changes would improve the accuracy of the arterial velocity?

a. decrease the pulse repetition frequency; decrease the Doppler gain

b. angle the sample volume; adjust angle correction to blood flow

c. angle the color box; angle the sample volume; decrease the Doppler gain

d. decrease the pulse repetition frequency; adjust angle correction to blood flow

5. Mirror imaging artifact is a result of a(n):

a. weak reflector

b. strong reflector

c. impedance difference

d. strong attenuating structure

6. Approximately what percentage of the sound beam will reflect from a media boundary with perpendicular incidence, if the impedances are different?

a. 1

b. 10

c. 50

d. 99

7. Placement of an echo is determined by the reflec­tor’s round-trip time and:

a. density

b. stiffness

c. amplitude

d. propagation speed

find the cost of your paper

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